BiFeO3におけるストレスを駆動する形質的相境界です
R J Zeches1, M D Rossell, J X Zhang
1Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA 94720, USA. rzeches@berkeley.edu
Science (New York, N.Y.)
|December 8, 2009
まとめ
研究者らは,モルフォトロプ的相境界を作り出すことにより,新しい無鉛のピエゾ電気材料であるビスムートフェライトを開発しました. この材料は,相間を切り替えることができ,データストレージとアクチュエータアプリケーションの可能性を示しています.
科学分野:
- 材料科学 材料科学とは
- 固体物理 固体物理学
- ナノテクノロジー ナノテクノロジー
背景:
- ピエゾ電気材料は,機械的なエネルギーを電気エネルギーに変換します.
- モルフォトロプ的相境界は,高電気機械的結合の鍵である.
- 無鉛のピエゾ電気の代替品が必要である.
研究 の 目的:
- ビスムートフェライトを用いた無鉛のピエゾ電気材料の設計.
- ビスムートフェライトフィルムに形質的相境界を作り出すために.
- デバイスアプリケーションの潜在能力を探求する.
主な方法:
- エピタキシアル成長技術が採用されました.
- 理論的アプローチは,実験と組み合わせて使用されました.
- 電場に依存する研究が行われました.
主要な成果:
- 鉛のないビスムートフェライトフィルムで,表軸制約によって,形質的相境界が成功裏に形成されました.
- テトラゴナル型とロンボエドール型の相の間の可逆的な切り替えが観察されました.
- 測定可能な表面の移位は,フェーズスイッチング中に発生しました.
結論:
- エピタキシアル制約は,ビスムートフェライトの形態変性相境界形成を可能にします.
- この無鉛のピエゾ電気システムは,探査ベースのデータストレージに期待されています.
- 潜在的な応用には,高度なアクチュエータ技術が含まれます.
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